Thermal Cavity Closer

Thermo-loc Platinum Multi Cavity Closer - designed to eliminate damp and cold bridging around doors, windows, and sills.  Suitable for a range of cavity sizes up to 150mm by easily cutting to size using the pre-cut grooves. ...
Grouped product items
Product Code Cavity Width Length Price Available Qty
32885 50 - 100mm 2.4m
In Stock
  • Buy 10 for £6.84 each
69696 105 - 150mm 2.4m
In Stock
  • Buy 10 for £10.04 each

The Thermo-loc Platinum Multi Cavity Closer is suitable for cavities between 50-to-100mm and 100-to-150mm and is designed to:

  1. Close the cavity at external doors, window jambs and sills.
  2. Provide thermal insulation and prevent ‘cold bridging’.
  3. Provide an effective DPC and thermal barrier between external doors, window jambs or sills.

This cavity closer is durable, resistant to decay, exceeds the minimum thermal resistance path of 0.45m2 K/W stipulated in accredited construction details, and has a thermal conductivity of 0.031W/mK.

The Thermo-loc Platinum Multi Cavity Closer is compliant with Building Regulation Approved Documents C, L1 and L2, satisfies BRE document ‘Thermal Insulation: avoiding risks’ and meets all relevant British and NHBC standards.

The pre-cut grooves allow for quick and easy cutting so you can install the cavity closer onsite, and simple trimming helps to cope with ‘rogue’ cavity widths.

The Thermo-loc Platinum Multi Cavity Closer also exceeds the rigid profile extrusion, which allows it to be used in second fix applications.

Further benefits include:

  1. Global warming potential of less than 5
  2. Ozone depletion potential of zero

Cavity Closer Installation

  • Before installation, please note that the accredited construction detail published by DCLG requires a minimum overlap of 30mm between the window frame and cavity closer.
  • If being used in a second fix application, the cavity closer should be pushed into the open cavity after building work is complete.
  • The compressible nature of the exposed insulation material is used to create a friction fit in the cavity. Alternatively, you can trim the insulation to fit using a sharp knife.
  • Cut the cavity closer into required lengths allowing the jamb section to overlap the sill section by cutting away parts of the fixing flange and butt the underside of the lintel.
  • In order to ensure a secure fit, it’s recommended to fix nails to the flanges.
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